Make a matrix G so that each element in G is another matrix with a constant dimension (i.e. 3 by 3). Hence a 3 by 3 G would mean each element in G is a 3 by 3 matrix. With a total of 9 matrices in G. Or a 6 by 6 G would mean each element in G for which there are 36 are 36 matrices each of which is 3 by 3. If so than how about making each element in a matrix, vectors with a fixed dimension? So a 6 by 6 matrix would have 36 vectors with a fixed dimension. Then matrices like G can be operated on just like scalar matrices but care has to be taken when considering the dimensions of the matrix elements in G. But when all this has been taken into account than would it all be okay?